Processing apparatus of the dip-and-dunk type are well known. They commonly consist of a series of deep processing tanks which are arranged in a predetermined order which is related to the photographic processing stages, i.e. developer, bleach, fix, wash, wash and wash.
Photographic material to be processed, either in the form of film or paper, is attached to a support so that it hangs vertically over the deep processing tanks. The support and any attached photographic material is mounted so that it can be progressed along the tank line starting at the developer stage and finishing with the washing stages. Some apparatus incorporate a dryer stage after the wet stages.
In apparatus of the type described above, the material being processed has to follow a predetermined sequence as the support is moved from the start to the end of the machine. This does not allow the material to pass back to a previously visited processing stage.